Methylolated reaction product of a hydroxy carbamate and cellulose-dyeing dyestuff containing vinyl sulfone groups

ABSTRACT

The invention provides a cellulose-dyeing dyestuff having the formula ##EQU1## wherein Z is the chromophoric radical of a cellulose-dyeing dyestuff containing a vinyl sulfone group (--CH 2  CH 2  SO 2  --), e.g. Cl Reactive Violet 4 and Cl Reactive Black 5; B is --CH 2  CH 2  --, --CH 2  CH 2  CH 2  --, or ##EQU2## A is --O-- or --S--; and X is --H, --CH 2  OH, --CH 2  OCH 3 , or ##EQU3## which dyestuff will dye a cellulosic material by heating in the presence of an acid catalyst. The cellulose-dyeing dyestuff of the invention is prepared by reacting a conventional cellulose-dyeing dyestuff having a chromophoric radical containing the aforesaid vinyl sulfone groups (e.g., Cl Reactive Black 5 and Cl Reactive Violet 4) with a hydroxy carbamate, and methylolating the resulting product. The utility of conventional cellulose-dyeing dyestuffs, which are normally reactive with cellulosic materials under alkaline conditions, is greatly extended by converting them to the methylolated derivatives of the invention, through prolonged shelf life and compatibility with selected acidic catalysts.

This application is a division of Ser. No. 143,168 filed May 13, 1971,now U.S. Pat. No. 3,873,513, which was a division of Ser. No. 791,697,filed Aug. 6, 1968, now abandoned.

This invention relates to dyestuffs useful in dyeing cellulosictextiles. Specifically this invention relates to a wide variety of dyeswhich are generally applied to cotton and other cellulose containingtextiles from acid media, to the preparation of the said wide variety ofdyes, and to the application of these new colorants to cotton and othercellulose containing textiles. More specifically, this invention relatesto dyestuffs which are converted from alkaline reactive dyes toderivatives of the same dyes that are reactive under acidic conditions.

The instant invention teaches to those who would practice the inventionthat the dyestuffs produced by the method of the instant invention (1)can be applied from acidic medium, (2) can be stored indefinitely withthe selected catalyst incorporated in the solution and without thedyestuff suffering decomposition, and (3) when applied to cellulosictextiles the fixation of the colorant onto the textile can be postponedindefinitely.

The advantage to (1) the application of the dyestuff from acidic mediumis that a dye which is normally applied from basic medium can beconverted to application in acid medium in order to incorporate apreferred acid catalyst. The advantage to (2) being able to store theprepared dyebath is that if a solution containing all the ingredients isstored without this advance to the state of the art the dyestuff maysuffer decomposition, whereas a solution prepared by the method of theinstant invention would have excellent "shelf life." One advantage to(3) postponement of the fixation of colorant onto the cellulosic textileis that if the stored textile contains an impregnated colorant which isnot fixed said colorant can be removed without harm of any sort to thefabric.

The science and technology of textile dyeing have advanced so thatdyestuffs are available which are reactive with the textile material soas to produce a covalent bond between the textile substrate and thedyestuff. A number of reactive dyes for cellulosics are well known tothose skilled in the textile processing art. Among these arechloro-pyrimidine, chloro-triazine, vinyl sulfone, and acrylamide typereactive dyes, all of which are applied to the cellulosic textile underalkaline conditions.

In the prior art we find few reactive dyes available for applicationunder acidic conditions. Chromophore-containing derivatives of epoxy,aziridinyl, and triazinone compounds (see U.S. Pat. No. 3,152,111) havebeen described which can be applied under acidic catalysis to colorcellulosics. The reactive functions in these dyes are similar to thosefound in certain textile finishing agents. Problems associated with eachtype of functions are well known to those skilled in the art, namely,water and storage stability for epoxy and aziridinyl compounds and therelatively poor durability of triazinone finishes.

In the prior art we find that inventor Stanley discloses in U.S. Pat.No. 3,248,379 a somewhat related dyestuff. On cursory view of the citeddye structure the unskilled may indicate a kinship of the Stanley dye,column 1, lines 51-54, to the structure of the dyes of the instantinvention; however, the structures are different, as shown below.

    ______________________________________                                        The instant invention:                                                                      ##STR1##    X can be H or a  CH.sub.2 OH group                                            R = alkylene or                                                               substituted alkylene                                U.S. Patent 3,248,379:                                                                      ##STR2##    R' = alkyl                                          ______________________________________                                    

The instant invention discloses a carbamate with the colored moietyattached to the ester portion of the molecule, whereas U.S. Pat. No.3,248,379 discloses the colored moiety attached to the amide portion ofthe molecule.

The main object of the instant invention is to provide a new class ofdyestuffs containing an N-hydroxymethyl-substituted carbamate in whichthe chromophoric moiety is attached through the ester group of thecarbamate structure.

The second object of the instant invention is to provide stabilityagainst hydrolysis of a dyestuff in the presence of water.

The third object of the instant invention is to provide for postponementof fixation on a dyestuff applied on a substrate.

Other objects and further scope of the applicability of the instantinvention will become apparent upon reading the detailed descriptionthroughout the specification. As an example, rather than the dye moiety,the moiety could readily comprise other substituent groups capable ofimparting select properties, such as bactericidal character, waterrepellency, soil repellency, oil repellency, and other useful propertiesto the substrate.

Among the advantages of the present invention are potentially lower costbecause of lower cost intermediates, relatively mild acidic catalystsneeded in application to cellulosic material, the outstanding durabilityof the color because of the particularly stable amidomethyl etherlinkage to cellulose which methylolated carbamates produce, andexcellent stability of the dyestuff in water or on fabric subsequent toreaction with the substrate.

In accordance with this invention, cellulose-dyeing dyestuffs of thefollowing formula have been discovered: ##STR3## wherein Z is thechromophoric radical of a cellulose-dyeing dyestuff containing a vinylsulfone group (--CH₂ CH₂ SO₂ --), e.g., Cl Reactive Violet 4 and ClReactive Black 5; B is --CH₂ CH₂ --, --CH₂ CH₂ CH₂ --, or ##STR4## A is--O-- or --S--; and X is --H, --CH₂ OH, --CH₂ OCH₃, or ##STR5##

The new dyestuffs are made by the interaction of the vinyl sulfone groupcontained in the chromophoric radical of the dyestuff, such groupcontaining active sulfone groups, active vinyl groups, and the like witha hydroxy carbamate to form a dyestuff intermediate having a carbamatestructure attached thereto. This intermediate is methylolated with atleast a molar equivalent of formaldehyde to form the reactive dyestuffsof this invention.

Hydroxy carbamates suitable for use in this invention are compounds thatcontain but are not limited to the following structure: ##STR6## whereinA is --O-- or --S--, and B is --CH₂ CH--, --CH₂ CH₂ CH₂ --, or ##STR7##and x = 1 or more.

Some examples are: ##STR8## and ##STR9##

These carbamates can be prepared by substantially any of the knownprocesses for producing such compounds. In one such route, they can beprepared by reaction of ammonia with ethylene carbonate, substitutedethylene carbonate, or the thio derivatives.

Chromomorphic radicals of conventional cellulose-dying dyestuffssuitable for use in the preparation of dyestuff by this invention, arederived from compounds that contain but are not limited to the followingtype structures: ##STR10## wherein R is a member of the group consistingof HSO₃ --dye--OCH₂ CH₂ --, ##STR11## and ##STR12## and R' is a memberselected from the group consisting of CH₂ =CH--, --CH₂ CH₂ OH, --CH₂ CH₂OSO₃ H, --CH₂ CH₂ X (wherein X is any halogen) and --CH₂ CH₂ OCH₃.##STR13## wherein R is a member of a group consisting of NaSO₃--dye--NH--, a halogen, or ##SPC1##

and X is a halogen selected from a group consisting of chlorine,bromine, or fluorine. The manner in which the halotriazines are madedoes not in any way limit their utility in this invention. Some examplesof chlorotriazines are given below but the invention is not limited tothese examples: ##SPC2## ##SPC3##

The only limiting requirement of such chromophoric radical is that theycontain a functional group reactive to the hydroxyl group of thecarbamate structure.

In preparing the dyestuffs of the invention, the desired chromophoricradical is attached to the hydroxy carbamate by reaction to form theintermediate as shown hereunder. ##STR14## where Z is thecolor-containing moiety, Y is a group reactive to --OH, B is --CH₂ CH₂--, --CH₂ CH₂ CH₂ --, or ##STR15## x=1 or more, and A is --O-- or --S--.

Conveniently, the reaction is accomplished by adding to one mole of thehydroxy carbamate, a measured amount of the dyestuff in the absence ofwater and then making alkaline with sodium hydroxide. The measuredamount may be more than, equal to, or less than a molar equivalent ofthe hydroxy carbamate. The reaction mixture is then heated to anelevated temperature, conveniently on a steam bath, to form theintermediate. The intermediate need not be separated or isolated. Tothis solution is added neutralized formalin containing at least one ormore molar equivalents formaldehyde. The desiredN-hydroxymethyl-substituted carbamate dyestuff is formed according tothe following equations: ##STR16## or ##STR17##

In forming the N-hydroxymethyl-substituted carbamate dyestuffs, it ispreferable to carry out the reaction at a temperature above 20°C. Theresultant dyestuff is then acidified to a pH of 6.0 or less.

The new reactive dyestuffs of the invention are especially suited forthe coloration of cellulosic textile materials such as cotton, linen,and viscose rayon. Textile material containing a substantial amount ofcellulosic fiber blended with other fibers also may be treated by theprocess of this invention.

The dyestuffs are applied by treating the textile material in an aqueoussolution (which may be thickened as a printing paste) in the presence ofan acidic or latent acidic material such as zinc nitrate, magnesiumchloride, zinc fluoborate, zinc chloride, and the like. The acidiccatalyst may be added to the dye bath prior to, simultaneously with, orafter the addition of the dyestuff.

Dyeing in the presence of latent acidic catalyst preferably is carriedout at elevated temperatures, for example, between about 60° and 200°Cin order to improve the exhaustion and fixation of the dyestuff. It ispreferable to heat cellulosic materials at 120°C or higher for a shortperiod of time after application of the dyestuff and latent acidiccatalyst. The textile material may be dried if desired and stored forprolonged periods prior to dyestuff fixation. In this manner it becomespossible to readily remove the dyestuff and reapply.

To summarize, the present invention provides (I) a new class of reactivecolorants, (II) a method of preparing these new colorants, and (III) aprocess comprising postponement of fixation when these new colorants areapplied to cellulosic textiles. More specifically the invention can bedescribed as:

I. A dyestuff of the general formula ##STR18## wherein Z is thechromophoric radical of a cellulose-dyeing dyestuff containing a vinylsulfone group; B is --CH₂ CH₂ --, --CH₂ CH₂ CH₂ --, or ##STR19## A is--O-- or --S--; and X is --H, --CH₂ OH, --CH₂ OCH₃, or ##STR20##

II. A method of converting a cellulose-dyeing dyestuff which isgenerally reactive with hydroxyl groups under basic conditions to acellulose-dyeing dyestuff which is capable of reacting with hydroxylgroups under acidic conditions, comprising

a. mixing a cellulose-dyeing dyestuff having a chromophoric radicalcontaining a vinyl sulfone group with hydroxyalkyl carbamate in a weightto weight ratio of about 1:3, and adjusting the pH to about 8 to 10,

b. heating the mixture for about from 40 to 2880 minutes at temperaturesabout from 25° to 100°C., using the longer periods of time with thelower temperatures, to obtain a dyestuff intermediate,

c. cooling the intermediate to about 25°C (room temperature),

d. mixing the cooled intermediate of (c) with about from 2.3 to 4.6parts of a 36.3% formaldehyde solution (a molar ratio of about from 1:1to 1:2 of hydroxyalkyl carbamate to formaldehyde),

e. adjusting the pH of the mixture of (d) to about from 8 to 10,

f. heating the adjusted mixture for about from 30 to 45 minutes at about100°C to obtain the new reactive dyestuff, and allowing the mixture tocool to about 25°C,

g. adjusting the pH of the final mixture to below 7,

h. adding an acid-type catalyst to the adjusted final mixture, and

i. storing the catalyzed dyestuff mixture for an extended, indefiniteperiod of time until needed and without fear of hydrolysis of thedyestuff during storage; and

III. A process for facilitating postponement of fixation of reactivedyestuffs applied on cellulosic textiles, comprising:

a. impregnating the cellulosic textile with an aqueous solutioncontaining an acidic catalyst and a dyestuff of the general formula:##STR21## wherein Z is the chromophoric radical of a cellulose-dyeingdyestuff containing a vinyl sulfone group; B is --CH₂ CH₂ --, --CH₂ CH₂CH₂ --, or ##STR22## A is --O-- or --S--; and X is --H, --CH₂ OH, --CH₂OCH₃, or ##STR23## b. centrifuging the wet, impregnated textile toremove excess liquid, c. drying the wet, impregnated material for about7 minutes at about 60°C,

d. storing the dry, impregnated, cellulosic textile for about from 0 to70 days at ambient temperatures, and

e. heating the stored, dry, impregnated, cellulosic textile for aboutfrom 3 to 4 minutes at about 160°C to effect fixation.

The detailed description and specific examples while indicatingpreferred embodiments of the instant invention are provided only toillustrate the invention and should not be construed as limiting thescope of the instant invention in any manner whatever. Numerous changesand modifications within the spirit of the invention will becomeapparent to those skilled in the art.

EXAMPLE 1

3.5 grams of the yellow chromophore Cl Reactive Yellow 4, having theformula ##SPC4##

and providing the chromophoric radical ##SPC5##

containing the chlorotriazinyl group ##STR24## are added to 10.5 grams(0.1 mole) of hydroxyethyl carbamate and to this mixture is added sodiumhydroxide solution to make a pH of 8-10. The solution is heated on asteam cone for 40 minutes, then cooled to obtain the intermediate. Thereis then added 8 grams (0.1 mole) of neutralized 36.3% formalin and themixture is heated 30 minutes on a steam cone, cooled to roomtemperature, and allowed to stand 16 hours. The solution is adjusted tobelow pH 7 with 6N hydrochloric acid and allowed to stand until readyfor application.

To the above solution is added 76 ml distilled water and 4 ml of 25%zinc nitrate hexahydrate solution. An 80 × 80 cotton printcloth(Sample 1) is thoroughly saturated with the solution, centrifuged toremove excess liquid, then dried 7 minutes at 60°C and heated 3 minutesat 160°C for fixation, washed, and dried.

3.5 grams of said yellow chromophore containing chlorotriazinyl group(CI Reactive Yellow 4), the starting material, is added to a solutioncontaining 92.5 ml distilled water and 4 ml of 25% zinc nitratehexahydrate solution. The solution is acidified with 6N hydrochloricacid and applied to an 80 × 80 cotton printcloth (Sample 2) as done forSample 1. The fastness of the dye in Sample 1 was much greater than thatof the colorant of Sample 2.

EXAMPLE 2

The procedure of Example 1 is repeated using as a starting material thered chromophore Cl Reactive Red 7 having the formula ##SPC6##

and providing the chromophoric radical ##SPC7##

containing the chlorotriazinyl group ##STR25## The fastness of thedyeing to washing of the carbamate dyestuff is once again greater thanthat of the colorant from which the new dyestuff is prepared.

EXAMPLE 3 ##SPC8##

is added to 10.5 grams (0.1 mole) of hydroxyethyl carbamate and to thismixture is added sodium hydroxide solution to obtain a pH 8-10. Theingredients of the solution were allowed to react for 48 hours at 25°Cto obtain the intermediate. 16 grams (0.2 mole) of 36.3% formalin at pH10 is then added and the mixture is heated 45 minutes on a steam coneand the solution cooled. 82 ml of distilled water is added and the pHadjusted to 5.7 with a solution of hydrochloric acid and then 4 ml of25% zinc nitrate hexahydrate solution is added. The procedure to treatSample 1 was followed for Sample 5.

3.5 grams of CI Reactive Violet 4, the starting material is added to92.5 ml of distilled water and the pH adjusted to 5-6 with solution ofhydrochloric acid. 4 ml of 25% zinc nitrate hexahydrate solution is thenadded. The solution is then applied to Sample 6 following the procedurefor Sample 5. The fastness of the dye of Sample 5 to washing is muchgreater than that of the colorant from which the new dyestuff isprepared (Sample 6).

EXAMPLE 4

The procedure of Example 3 is repeated using CI Reactive ##SPC9##

groups, as a starting material. The fastness of the dyeing to washing ofthe new carbamate reactive dyestuff on fabric is greater than that ofthe colorant from which it is prepared.

EXAMPLE 5

The solution of Example 2 containing the new dyestuff and zinc nitratecatalyst is stored in a stoppered glass flask for 15 months then it isapplied to cotton printcloth following the procedure of Example 1. Afterdrying at 60°C for 7 minutes two portions of sample are removed and theremaining portion is heated 4 minutes at 160°C. One portion of the driedsample is washed and dried with the portion heated to 160°C. Thefastness of the dyeing to washing is far greater for the portion heatedat 160°C than the other portion. This illustrates the stability of thenew dyestuffs in the presence of water and acidic catalyst overprolonged periods of time. It also illustrates the ease of removal ofthe dye prior to fixation at an elevated temperature. It also shows thatthe reaction to cause chemical union between the dyestuff and thecellulose occurs at elevated temperature and that fastness is notachieved until this chemical union occurs.

The third portion, dried only, was stored 10 weeks then cut into twoparts. One part was heated 4 minutes at 160°C to effect dye fixation.The remaining part of the dried sample is washed and dried with the partheated to 160°C. The fastness of the dye to washing is far greater forthe part heated at 160°C than the other part. Further, the fastness ofthe dye to washing is the same as the sample heated to 160°C immediatelyafter drying.

EXAMPLE 6

The procedure of Example 5 was repeated using the solution of Example 4which is stored 15 months in presence of water and acidic catalyst. Thefastness of dyeing to washing was again greater for the heat fixedsample compared to the non-heat fixed sample.

We claim:
 1. A dyestuff having the formula ##EQU4## wherein Z is thechromophoric radical ##SPC10##--CH₂ CH₂ CH₂ --, or ##EQU5## A is --O--or --S--; and X is --H, --CH₂ OH, --CH₂ OCH₃, or ##EQU6##
 2. Thedyestuff of claim 1 wherein Z is ##SPC11##B is --CH₂ CH₂ --; A is --O--;and X is --CH₂ OH.